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What kind of MAF readings do you guys get?

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Old 09-03-2007, 09:46 PM
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Default What kind of MAF readings do you guys get?

What kind of MAF readings do you guys get?
Less than 250 or higher than 1000 gr/sec?

I have searched this site and have seen several posts with people reporting mass flows in the thousands of grams per second .

I am looking at high readings on a stock 93 L67 using a CP9110.
At idle I get 1500 gr/sec, cruising on highway I see 3~4000 gr/sec, and have seen more than 15~20,000 at higher throttle.

I have a ’92 FSM and it says TECH 1 should give values ranging from 0 to 255.9 gr/sec and that a typical value with warm L67 idling should be around 4.9 gr/sec.

If you calculate what the mass flow should be based on engine displacement, RPM, and boost you get something close to the 4.9 grams/sec at idle. The 255 upper limit corresponds to something like 5000 RPM at 5~10 psi boost and injector flow of 23 lb/hr at 14.7 A/F ratio.

The GM range of flows look somewhat reasonable.
MAF readings 10~100 times higher don’t make sense no matter what mods you have.

So -- I am curious as to what is going on.
Is there some bug in the Actron scanners? Is there a bug in the PCM? Do I (and possibly others) have a problem with sensor/PCM?

What are your experiences?
Old 09-04-2007, 07:23 AM
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I believe my LQ4 maf is tuned to see 0-11,000
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